9 th International Conference on Instrumental Methods of Analysis: Modern Trends and Applications, Kalamata, Greece, 20 - 24 September 2015, pp.302
Among the available adsorbents, nanosized metal oxides (NMOs), including
nanosized ferric oxides, manganese oxides, aluminum oxides, titanium oxides,
magnesium oxides and cerium oxides, are classified as the promising ones for heavy
metals removal from aqueous systems. This is partly because of their large surface
areas and high activities caused by the size quantization effect. Recent studies
suggested that many NMOs exhibit very favorable sorption to heavy metals in terms
of high capacity and selectivity, which would result in deep removal of toxic metals
to meet increasingly strict regulations. They are present in different forms, such as
particles, tubes and others. The size and shape of NMOs are both important factors to
affect their adsorption performance. In recent years, these materials have been
proposed and used in the preconcentration of trace metals due to their high surface
area, high adsorption capacity and high chemical activity [1,2].
In this study, nanosized urchin-like NiCo2O4 adsorbent was synthesized and
characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).
NiCo2O4 as a promising mixed-metal oxide has been widely investigated for
potential applications in lithium-ion batteries, supercapacitors, electrocatalysts, and
optoelectronic devices . The nanosized urchin-like NiCo2O4 was used for the first
time as an adsorbent for the preconcentration of the Pb(II) ions in various samples.
The effect of experimental parameters such as pH, contact time, eluent type and
volume, sample volume, adsorption capacity and matrix effect was investigated. pH
was found to be 4. The elution was easily made with 2 mL of 2.5 mol L−1 HCl. The
recovery values for Pb(II) were found to be ≥90% in the presence of 10000 mg L−1
Na(I), 10000 mg L−1 K(I), 5000 mg L−1 Mg(II) and 7500 mg L−1 Ca(II).